Astrocytes pp 155-168 | Cite as

In Vitro Engulfment Assay to Measure Phagocytic Activity of Astrocytes Using Synaptosomes

  • Youkyeong Gloria Byun
  • Won-Suk ChungEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1938)


Astrocytes eliminate unnecessary synapses, neural debris, and pathogenic proteins such as amyloid β plaque. Although the emerging evidences suggest that the phagocytic roles of astrocytes are critical in maintaining brain homeostasis during development as well as pathogenic conditions, the efficient assay for measuring phagocytic capacity and kinetics of astrocytes has been lacking. Here we present in vitro engulfment assay using purified astrocytes and synaptosomes. Based on imaging methods, either fluorescent or pH indicator-conjugated synaptosomes can be used in this assay.

Key words

Astrocytes Phagocytosis Engulfment Degradation pH indicator Synaptosomes Confocal microscope Live imaging 



The authors thank all members in Chung’s laboratory for helpful discussion. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIP) (NRF-2016M3C7A1905391,NRF-2016R1C1B3006969, and NRF-2018R1A4A1020922) (W.-S. C).


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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Biological SciencesKorea Advanced Institute of Science and TechnologyDaejeonRepublic of Korea

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